Piano-action



(No Model.)

Patented July 22, 1890.

w w J 2 Sheets-Sheet. 2. A. D. DIMIGK.

PIANO ACTION.

(No Model.)

Patented July 22, 1890.

lr i

MTA/EJSEE.

UNITED STATES PATENT OF ICE.

AUGUSTUS D. DIMICK, OF WAKEFIELD, MASSACHUSE'FS.

PIANO-ACTION.

SPECIFICATION forming part of Letters Patent No. 432,516, dated July 22. 1890.

Application filed January 30, 1890. Serial No. 338,596. (No model.) 7

To all whom it may concern.-

Be it known that I, AUGUSTUS D. DIMIcK, a citizen of the United States, rcsidingat akefield, in the county of Middlcsex and State of Massachusetts, have invented certain new and useful Improvements in Piano-Actions; and I do hereby declare the following; to be afull, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The invention relates to pianos in general, and has particular reference to the mechan ism whereby the hammers are caused to deliver the blow upon the strings, technically known as the action.

It relates especially to vert'ically-arranged actions designed for use in upright pianos, and has for its objects to cheapen the cost of manufacture, to simplify the construction, to reduce the number of parts, to avoid the use as far as possible of objectionable pivots, and to secure a more direct and positive action of the several pieces composing the action, wherebyfriction is reduced to a minimum and a noiseless, easy, and sensitive operation of the parts is obtained, and firmness and precision of action are secured, together with the requisite capability for quick rcpetition of the stroke of the hammer.

To this end the invention consists in the construction and arrangement of parts hereinafter described and claimed, embodying as distinguishing characteristics a jack, which,

instead of being pivoted upon a bed or jacklever interposed between it and the key, is arranged to slide bodily up and down in or upon suitable guides on the action-rail, and has an adjustable knob on its lowerend, the jack being operated by a direct connection with the key; a damper, which, instead of being pivoted midway of its length and operated by a lifter on the jack bed or lever acting between the damper-lever and the action-rail, is pivotally mounted at its lower end and operated by a lifter on the key acting on the opposite side of the damper-lever from the rail; an adjust-- able stop for the lifter rod, whereby the amount of liberty or clearance between it and the damper-lever may be regulated in connection with a lifter-rod acting on the outer side of the lever; a back-check for the ham mcr, which, instead of being mounted on the jack bed or lever and acting upon a buffer or hunter projecting from the ham iner-but-t near its pivot, is arranged to slide in bearings in the action-rails, and acts upon an extension of the hammer-head, being actuated by the upward movement of the jack itself, and also in minor features and details of construction which will be more particularly hereinafter pointed out in the claims.

In the accompanying drawings, forming part of this specification, Figures 1 and 2 are side views of the action, (the rails only being in section,) the parts being in different positions. Figs. 3 and 5 are detail views of modifications of certain of the connections, and Fig. 4 a detail of an improved key-pad.

Like letters designate corresponding parts in the several figures.

A is the key, pivoted, as usual, about midway of its length, and provided under its ends with pads a, which may be the ordinary pieces of cloth or felt, as shown in Figs. 1 and 2; or, if preferred, of the kind shown in Fig. 4, to be hereinafter described.

B is the main rail of the action; C, the hammer-rail; D, the damper-check rail,to which the usual hammer and damper-springs are attached; E, the lower rail, to which the damper-lever is pivoted, and which has an integral or attached flange c to guide and help sustain the jack, and H a light railforming a guide for the lower end of the hammercheck'rod and carrying the jack-springs.

F is the hammer-head, provided with the extension f, for a purpose to be hereinafter described, the hammer being pivoted at its butt f, by means of the metal clip f, to a flange on the top edge of the main action-rail, said clip passing around the pivot-pin in the flange, this clip being, in this invention, given the particular construction shown, for a purpose presently to be described.

G is the jack, which, as above stated, instead of being L-shaped, is made of a straight continuous piece, preferably widened out at some point intermediate of its ends, as shown at g, and slotted at that place, (this slot having, preferably, like the others, a soft bushing,) so as to take over and be supported mainly by a pin 7, projecting from the actionrail, so as to be capable of a sliding movement up and. down under the action of the key. The lower end of the jack, instead of being pivoted to the usual jack bed or lever, is passed through a bushed slot in the lower rail E and stepped directly upon the key itself, thereby dispensing entirely with the jack-bed or other intermediate mechanism IO between the jack and the key and obtaining a more direct and positive thrust upon the hammer with a quicker response to the touch on the key. The upper part of the jack extends up between the action-rail l3 and the light rail II, which is carried by studs g, projecting from the main rail, and forms the lower guide-bearing for the sliding hammercheck rod. The nose or upper end of the jack is held normally forward, so as to engage the padded shoulder on the hammerbutt by the expansion-spring.71, fixed to the rail II, though it may be similarly operated bya small contraction-spring fastened at one end to the opposite side of the jack and secured at the other to the action-rail.

In order to trip the jack to permit the re turn of the hammer after the delivery of the blow, I use a let-off composed of an adjustable stop '1', whose stem is screwed into the 0 jack near its upper end, in connection with a tang or lug on the hammer-butt. I conveniently make use of the clip f by which the butt is pivoted on the pin of its flange, to form this tangor lug. The clip is therefore longer 5 than usual, and is shaped as shown, so that as the hammer moves forward it will at the proper time engage the step i in the jack and trip the latter. By making the stop adjustable the point in the movement of the ham- 0 mer where the tripping takes place may be regulated with exactness.

To preventthe jack when tripped from getting farther away from under the shoulder of the hammer-butt than is necessary, thereby 5 causing excess of liberty or movement of the jack and requiring extra work for its returning spring 72, as well as to accurately control this liberty of the jack, I provide the pin 9 with an adjustable padded head or button 71 Upon the threaded rod g in the lower .end of the jack, where it passes through the slot in the rail E, I place another adjustable button 71. which limits the downward movement of the jack and prevents the action falling when 5 the key is removed.

The connection between the key and the lower end of the jack may be made in different ways, of which I have shown two in the drawings. In Figs. 1 and 2 there is let into thekey a piece of hardwood a, having in its upper surface a hemispherical recess, into which fits arounded knob, of rubber or other suitable material, on the lower end of the button I, which, moreover, is made adj ustable by 6 5 screwing on the rod to effectalterations in the length of the jack. It is obvious, however, that the parts might be reversedthat is, the knob be arranged on the piece a and the hemispherical recess in the end of the button I.

Fig. 5 shows a modiiimrtion of the abovedescribed arrangement. In this form the screw-rod and its button and adjustable step are dispensed with, and the lower part of the jack is provided with a key-hole slot taking over a headed pin, which takes the place of the flange on the rail E. The end of the jack is forked, and straddles a pivot-pin in a rocker mounted on the key. Other modifications will suggest themselves to the skilled operator.

As before stated, the damper-lever.l,instcad of being pi yoted midway oi. its length andoperated by a lifter mounted on the jack-bed and acting bet-ween the lever and the rail, is pivotally mounted at its lower end upon the rail E, preferably by a flange secured thereto, and actuated by a lifter L, mounted on the key and bearing on the outside of the lever at about the middle of its length, resulting in a direct lifting of the damper by thekey, giving a quicker, easier, and surer action. This lifter is shown in Figs. 1 and 2 as a pad on the upper end of a vertical rod iixed in the key. The pad may, however, be fixed on the upper end of a rocker, as shownin Fig. 3, and be adjustable in that way instead of bybending the red, as in the other construction, or it might even have an adjustable button, like that used in the jack at '1'. The lever is guided near its upper end by a headed pin from the action-rail passing through a keyhole slot in the lever. By unscrewing the flange at the foot of the lever and dropping it slightly it may be taken off of the pin.

Instead of mounting the lifter-rod K between the damper-lever and the rail, which arrangement requires a considerable cutting away of the latter and gives much trouble and annoyance in getting at the parts to adjust the liberty or clearance of the rod, I arrange it on the outer side of the lever and connect it with the action-rail by pivoted links I, as shown, whereby ready accessis had to the rod, and the rail, not beingcut away, is strengthened. v

To limit. the outward movement of the rod and to adjust it for the purpose of giving it the proper clearance, I provide an adjustable catch or hook-shaped sto p S, which is screwed into the action-rail and may be adjusted by turning in or out, so as to set the bar at asuitable distance from the damper-lever to permit the proper action of the damper on the strings.

The back-check for the hammer has heretofore generally been mounted on the jack bed or lever and arranged to act on a buffer projecting from the hammer-butt. In this invention it is, however, arranged in sliding bearings in the action-rails, and consists of a rod 0, whose padded upper end extends above the hammer-rail and plays in the path of the The shape and structure of the extension may be varied within wide limits, as I do not wish to be confined to the shape shown. Any other form or configuration maybe resorted to which experience may demonstrate to be more efficient or desirable Figs. 1 and 2 show the form of key-pad in common use, being a piece of thick felt. This is somewhat objectionable on account of be ing affected unfavorably by atmospheric changes, thereby interfering with the free and easy action of the key.

In Fig. at I show a form of pad or rest which is not affected by moisture or temperature.

It consists of a rubber cord or rod 0, set into a groove in the piece (I and covered by a strip of light felt or any suitable cloth I). While I have shown it in connection with the key, it could be used, if desired, on the ham mer-check rail or other point where a clieck pad of this character is desired.

The construction of my improved action being as above described, the operation is generally as follows: The depression of the key raises the jack, the damper-lift, and the hammer-check, freeing the damper from contact with the strings, throwing the hammer forward to deliver the blow, and carrying the hammer-check into a position where it will be engaged by the hammer-head projection after the blow has been given, in order to prevent the rebound of the hammer. As the hammer moves forward, the tang or lug f moves in the opposite direction, and striking the stop '6 on the jack trips the latter, allowing the hammer to return. The j ack-spring h acts to restore the jack to its normal position promptly, whereby quick repetitions of the blow may be given with less than the full stroke of the hammer.

It is apparent that many of the details of the construction and arrangement of the several parts of my action may be considerably varied; also, that some of the features may be used without employing the whole.

It is to be understood that the rockers shown in the modifications in Figs. 3 and 5 are fixtures on, and, so far as this invention goes, are parts of the key.

Having thus described my invention, what I claim, and wish to secure by Letters Patent, 1s-

1. In a piano-action, the combination of the main action-rail, the lower rail, the jack sliding in suitable guides or ways on the rails,

and the key, the jack resting directly upon the key and having an adjustable knob on its lower end, substantially as described.

2. The combination of the key,the pivoted hammer, the sliding jack, the jack-trip consisting of the adjustable stop in the jack and the tang on the hammer-butt and the jackspring,the jack arranged to slide endwise on suitable guides in the action-rail, the spring arranged to restore the jack to place afterit has been tripped,and means to limit the lateral movement of the jack, substantially as described.

3. The combination of the main action-rail, the lower rail, the pin from the former and the slot in the latter, the sliding jack having a vertical slot in its body taking over the pin and the lower end of the jack playing in the slot in the lower rail, adjustable buttons on the lower end of the jack, and the pin in the main rail, substantially as described.

4. The combination of the main and lower rails, the pin from the former and the slot in the latter, the sliding jack having a slot taking over the pin and having its lower end playing in the slot in the lower rail, the pivoted hammer, and the sliding hannner-check rod, the lower part of the jack being provided with an adjustable stop bearing upon the lower rail to prevent the action falling too low, substantially as described.

5. The combination of the main rail, the ham trier-flange secured thereto,and the hammer-butt, the latter connected to the pivotpin in the flange by the plate f passing around the pin and having its end elongated and bent backward, as shown, to act as the jack-trip, substantially as described.

6. The combination of the key and the jack, the key having a piece of hard wood a let into its upper surface and having a hemispherical recess, and a rounded knob on the end of the jack seated in the recess, substantially as described.

7. The combination of the key, the damper-lever pivoted at its lower end to one of the action-rails, and the damper-lift mounted on the key and acting upon the outer or back side of the lever, substantially as described.

8. The combination of the pivoted damperlever and the lifter-rod, link connected to the action-rail and lying outside or back of the damperdever, substantially as described.

9. The combination of the pivoted damperlever, the lifter-rod, link connected to the action-rail and lying outside of the damperlever, and an adjustable catch to set the rod in proper position for the action of the damper, substantially as described.

10. The combination of the hammer-head, its extension, the sliding jack, the sliding l1a1nmercheck, and the key, the check being actuated by the jack and the latter being 0perated directly by the key, substantially as described.

11. The combination of the hammer-head, its extension, the jack, and the hammer-check,

the latter being arranged to be operated by In testimony whereof I affix my signature the jack, snbsmnijialiy as described. in PI'OSOHC'O of two witnesses.

12. The cmnbinnt-ion 0f theinnnmcr-chec i rail and the rail ILiihe imnnnewhond with its AUGUSTUS D. DIMICK. 5 extension, the jack, and the lnunnwr-check \Vitnesses:

rod sliding in hearings in the mils and opur- HERBERT W. ELMOHE,

mod by the jack, substantially as described. .I. A. GOLDSBORUU(1H. 

